Various intravascular deliverable devices are used for treating specific conditions via access through body lumina, such as patient's circulatory system. The target site may for instance be an atrial or ventricular septum having a defective opening to be occluded, such as devices for treating septal defects and the like. In certain circumstances, it may be necessary to occlude a patient's lumen, vessel, chamber, channel, hole, or cavity such as to stop blood flow there through. One such condition known in the art is Para-Valvular Leak (PVL) which may occur in association with surgical implantation of prosthetic valves in the heart, and with interventional valve implantations in general, i.e. transcatheter aortic valve intervention (TAVI). When the prosthetic valve is fixed by sutures micro-holes are created where the sutures penetrate the tissue. These micro-holes can become dilated over time and grow larger and also merge together, thereby creating undesired blood passages around the valve compromising the normal flow of blood through the valve. Any surgical procedure around the valve may create such undesired leaks. Whether it is implantation of a prosthetic valve or procedures around the native heart valve, sutures or other means that must penetrate the surrounding tissue may be the source of such leaks. Leaks around the valve may also arise because of other undesired conditions. For example, after the replacement of the valve the pressure increases which could cause damages on the degenerated tissue around the valve area, such that leaks occur. That tissue can also be perforated with guide wires or guiding catheters during any other heart surgery procedure, with leaks as a consequence.
In the case of prosthetic valves, over 210.000 valve replacements are performed each year world wide. In between 3-12% of the operations there is paravalvular leakage, and 3-4% is critical and needs reoperation. The diagnosis of paravalvular leak is done during the first year of the implantation. The patient may have a small PVL that may not effect the blood transfusion but can be diagnosed with imaging techniques such as TEE. Usually surgical therapy is the standard for treating paravalvular leaks but reoperation increases mortality and morbidity as compared to the first operation, i.e. reoperation is more difficult and increases the risk factor. After surgical reoperations 20% of the patients has residual or recurrent paravalvular leak. Another possibility is to use medical therapy, which is palative, i.e. the symptoms can be decreased but hemodynamic anomalies can not be regulated.
Occlusion devices exist that are used for treating PVL. FIGS. 1a-b shows such occlusion device when positioned at the periphery of the prosthetic valve from an atrial view (FIG. 1a) and from a ventricular view (FIG. 1b). The occlusion device has portions positioned on either side of the valve.
A problem with such previous occlusion devices is the disruption of the blood flow they create. Disruption of the blood flow is increasing risks for the patient for other complications and is detrimental to patient safety. The disruption can cause turbulence in the blood flow, which could increase the risks of embolies.
A further problem is the insufficient sealing that previous occlusion devices provide. Insufficient sealing may lead to further reoperations and unnecessary complications for the patient.
Another problem with the previous occlusion devices is the inability to adapt to the irregular and varying anatomy of the implantation site. Conformation to varying anatomies is critical for secure deployment of the occlusion device, without having to risk dislodgement and/or insufficient sealing.
A further problem with previous devices is problems with orientation and delivery of the device. Proper orientation is important for achieving the correct function of the device, and also for ease of the procedure.
All aforementioned problems affect not only patient safety but also available resources in the health care system as each patient will take longer to treat. Patient risks of previous paravalvular leak closure devices and methods include embolization of the device, stroke, arythmia, perforation of the biological prosthetic valve, and dysfunction of the valve prosthesis.
WO2008153872 discloses a device to be positioned on either side of the wall of a tubular blood vessel. Arcuate portions of the device conform to the tubular blood vessels surface.
Hence, an improved implant would be advantageous and in particular allowing for increased patient safety, flexibility, and/or cost-effectiveness would be advantageous.